The beginning of the Cambrian Period is marked by the evolution of hard body parts such as calcium carbonate shells. ... These body parts fossilize more easily than soft tissues, and thus the fossil record becomes much more complete after their appearance.
1.
C. Genus and species
Binominal nomenclature: a formal system of naming species of living things, such as humans which are <em>homo sapiens.</em>
2.
A. carbohydrates
any of a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose.
3.
C. work with other cells
one unicellular organism would quickly die if was not within a colony of very similar unicellular organisms.
4.
C. Bacteria
bacteria are able to cause contagious diseases seeing as a virus, (which can be a contagious disease) is a form of bacteria.
D because it is the correct one
Answer:
Explanation:
They catalyze the synthesis of short RNA molecules used as primers for DNA polymerases.